/Engine/Source/Runtime/Core/Public/Templates/SharedPointer.h
Special constructor used internally to statically cast one shared reference type to another. You should never call this constructor directly. Instead, use the StaticCastSharedRef() function. This constructor creates a shared reference as a shared reference to an existing shared reference after statically casting that reference's object. This constructor is needed for static casts.
template<typename OtherType> TSharedRef ( [TSharedRef](API\Runtime\Core\Templates\TSharedRef)< OtherType, Mode > const & InSharedRef, [SharedPointerInternals::FStaticCastTag](API\Runtime\Core\Templates\FStaticCastTag) )